TY - JOUR
T1 - A Pyrene-4,5,9,10-Tetraone-Based Covalent Organic Framework Delivers High Specific Capacity as a Li-Ion Positive Electrode
AU - Gao, Hui
AU - Neale, Alex R.
AU - Zhu, Qiang
AU - Bahri, Mounib
AU - Wang, Xue
AU - Yang, Haofan
AU - Xu, Yongjie
AU - Clowes, Rob
AU - Browning, Nigel D.
AU - Little, Marc A.
AU - Hardwick, Laurence J.
AU - Cooper, Andrew I.
PY - 2022/6/1
Y1 - 2022/6/1
N2 - Electrochemically active covalent organic frameworks (COFs) are promising electrode materials for Li-ion batteries. However, improving the specific capacities of COF-based electrodes requires materials with increased conductivity and a higher concentration of redox-active groups. Here, we designed a series of pyrene-4,5,9,10-tetraone COF (PT-COF) and carbon nanotube (CNT) composites (denoted as PT-COFX, where X = 10, 30, and 50 wt % of CNT) to address these challenges. Among the composites, PT-COF50 achieved a capacity of up to 280 mAh g-1 as normalized to the active COF material at a current density of 200 mA g-1, which is the highest capacity reported for a COF-based composite cathode electrode to date. Furthermore, PT-COF50 exhibited excellent rate performance, delivering a capacity of 229 mAh g-1 at 5000 mA g-1 (18.5C). Using operando Raman microscopy the reversible transformation of the redox-active carbonyl groups of PT-COF was determined, which rationalizes an overall 4 e-/4 Li+ redox process per pyrene-4,5,9,10-tetraone unit, accounting for its superior performance as a Li-ion battery electrode.
AB - Electrochemically active covalent organic frameworks (COFs) are promising electrode materials for Li-ion batteries. However, improving the specific capacities of COF-based electrodes requires materials with increased conductivity and a higher concentration of redox-active groups. Here, we designed a series of pyrene-4,5,9,10-tetraone COF (PT-COF) and carbon nanotube (CNT) composites (denoted as PT-COFX, where X = 10, 30, and 50 wt % of CNT) to address these challenges. Among the composites, PT-COF50 achieved a capacity of up to 280 mAh g-1 as normalized to the active COF material at a current density of 200 mA g-1, which is the highest capacity reported for a COF-based composite cathode electrode to date. Furthermore, PT-COF50 exhibited excellent rate performance, delivering a capacity of 229 mAh g-1 at 5000 mA g-1 (18.5C). Using operando Raman microscopy the reversible transformation of the redox-active carbonyl groups of PT-COF was determined, which rationalizes an overall 4 e-/4 Li+ redox process per pyrene-4,5,9,10-tetraone unit, accounting for its superior performance as a Li-ion battery electrode.
KW - porous materials
KW - Li-ion batteries
KW - electrochemistry
KW - Raman spectroscopy
KW - composite materials
KW - covalent organic frameworks
U2 - 10.1021/jacs.2c02196
DO - 10.1021/jacs.2c02196
M3 - Article
C2 - 35588159
SN - 0002-7863
VL - 144
SP - 9434
EP - 9442
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 21
ER -